Wafer expanding devices of this kind have conventionally been known in various structures, such as Japanese Unexamined Patent Publication S62-124911. The wafer expanding operation by such conventional wafer expanding devices will be described with reference to schematic views shown in FIG. 28A and FIG. 28B.
As shown in FIG. 28A, a wafer feeding plate 506 holds a wafer sheet 508 on the top face of which a plurality of wafer feed components 502 formed through dicing of a wafer are attached, and in this held state, the wafer sheet 508 is kept in a substantially horizontal posture, without sagging, and with a specified tension applied thereto. It is to be noted that such a wafer feed component 502 is exemplified by an IC component.
Moreover, as shown in FIG. 28A, the wafer feeding plate 506 in such a state is fed to a component feeder 501 equipped with a wafer expanding device, so that the wafer feeding plate 506 is held by a plate holding member 561 at its peripheral portion.
Then, as shown in FIG. 28B, in the component feeder 501, the plate holding member 561 is lowered so as to lower the wafer feeding plate 506 and to bring the lower face of the wafer sheet 508 into contact with an upper end portion of an expanding ring 563 that is a substantially ring-shaped member disposed below the wafer sheet 508, and after the contact is made, the wafer feeding plate 506 is further lowered so as to stretch the wafer sheet 508 substantially radially. By this, the wafer attached onto the wafer sheet 508 is expanded.
In such expanded state, the plate holding member 561 is stopped from being lowered, and the lower face of the wafer sheet 508 is pushed up by a component push-up device 520 as shown in FIG. 28B, so that one wafer feed component 502 in the expanded state is separated from the wafer sheet 508 and is made feedable by a suction head and the like.
After the respective wafer feed components 502 are supplied from the wafer feeding plate 506, the plate holding member 561 is lifted and the expansion is cancelled. However, when such expansion is applied, even the wafer sheet 508 which can elastically deform to some degree cannot perfectly regain its original state, and as a result has some slack. With the presence of such slack, shaking and vibration are transmitted to the wafer feed components 502 remaining on the wafer sheet 508 during transportation of the wafer feeding plate 506, which may result in component damage. Moreover, there are cases in which the wafer feeding plate 506 is housed in a magazine cassette once the wafer feed components 502 on the wafer sheet 508 are removed, and if the wafer sheet 508 has slack in such cases, the wafer sheet 508 may be caught on a transportation unit or the like, which may cause a problem that smooth component feeding is disturbed.
In order to solve such a problem, in the conventional component feeder 501, slack of the wafer sheet 508 generated after the expansion is removed by shrinking the wafer sheet 508 with use of a heating blow. For applying such a heating blow, the component feeder 501 is equipped with a heating blower device 530 for applying the heated blow by heating and blowing compressed air. It is to be noted that such a heating blower device 530 is disposed in such a way that the compressed air is heated and blown from the inside of the expanding ring 563 to the lower face of the wafer sheet 508.